Objective:To investigate the regulation mechanisms of the bone marrow mesenchymal stem cells on lymphocyte pro -liferation of type I diabetic rats .Methods:The rat bone marrow mesenchymal stem cells were isolated , cultured and identified and the effect on lymphocyte proliferation of type Ⅰdiabetic rat was observed by MTT assay , and analyze the CD 4 +CD25 +regulatory T cell ra-tio, cell cycle and apoptosis of type I diabetes rat by flow cytometric .Results:B and C groups was significantly lower than the absor-bance values of group A,the differences between the data were statistically significant (P<0.05), C group was significantly lower than group B absorbance values, the difference was significant (P<0.05);the CD4 +CD25 +regulatory T cells of B and C groups were sig-nificantly higher than group A, the differences of the data were statistically significant (P<0.05), the CD4 +CD25 +regulatory T cell ratio of C group significantly higher than that group B , the differences were statistically significant (P<0.05);the apoptosis levels of B and C groups were significantly higher than group A , the differences were statistically significant (P<0.05), the apoptosis levels of C group were significantly higher in group B , the differences were statistically significant (P<0.05).Conclusion:Bone marrow mesen-chymal stem cells can significantly inhibit lymphocyte proliferation of type Ⅰdiabetic rats, and it may regulate CD4 +CD25 +regulatory T cells, promote apoptosis, thereby affecting the immune function of T lymphocytes , and play its rejection.

Objective:To construct a nomogram model for spontaneous respiratory arrest prediction in nerocritical patients within 72 hours after brain injury for early identification of potential brain death organ donors.Methods:From October 2017 to May 2019, 127 hospitalized neurocritical patients (including traumatic brain injury and spontaneous cerebral hemorrhage) were prospectively enrolled and the parameters related to brain injury were dynamically recorded. Among them, the data from October 1, 2017 to May 31, 2018 were used for constructing the training set and the data from June 1, 2018 to January 31, 2019 for constructing the validation set. The occurrence of spontaneous respiratory arrest within 72 h after brain injury was regarded as the time interest point and grouping factor. The factors associated with spontaneous respiratory arrest were screened by univariate and multivariate analyses. Then the Nomogarm prediction model was developed and tested in the validation set.Results:Sixty-five patients entered the training set and another 62 cases were enrolled into the validation set. In training set, univariate and multivariate analyses indicated that midline shift ( OR=4.56, 95%CI: 1.87~19.21), absent of ambient cistern ( OR=4.83, 95%CI: 1.35~16.34), cough reflex ( OR=3.82, 95%CI: 1.15~12.42), intraventricular hemorrhage ( OR=3.16, 95%CI: 1.53~14.52) and serum Na + <125 mmol/L ( OR=3.06, 95%CI: 1.53~13.44) were associated with spontaneous respiratory within 72 h. In both sets, the predicted C index of spontaneous respiratory arrest rate within 72 h was 0.81 (95%CI: 0.76~0.85) and 0.80 (95%CI 0.75~0.83) respectively. Further statistical analysis implied that 140, 160 and 170 points were the dangerous dividing points and these three points were 30.1%, 65.6% and 93.4% associated with spontaneous respiratory arrest within 72 h respectively. Conclusions:Nomogram model based upon assessment parameters of brain injury may predict the time of spontaneous respiratory arrest in neurocritical patients. It can be used for early identification of potential brain death organ donors. The results require further external data validation.

Objective Parainfluenza virus is an important pathogen of lower respiratory tract infections in infants and young children.This study was to search for a method for rapid culture and identification of human parainfluenza viruses from nasal swabs. Methods Nasal swab specimens were collected from 0-5 years old children with acute respiratory tract infection.The specimens were inoculated onto 96 plates with prefabricated LLC-MK2 cells and then centrifuged for 1 hour at 3000 r/min and also inoculated using the traditional culture method, followed by addition of virus mainte-nance medium containing 4 μg/mL TPCK trypsin.The cytopathic effect was observed daily, and hemagglutination and blood absorption tests were done at 2, 5, and 8 days after inoculation.In case of posi-tive result of either test, the specimen was subjected to immunofluo-rescence staining. Results Six strains of parainfluenza virus were isolated from the 83 nasal swab specimens, with a positive rate of 7.2%.There was a significant difference in the rate of separation be-tween the rapid and traditional culture methods after 2 days of culturing (7.2%vs 0%, P<0.05).The infected cells produced a cy-topathic effect that characterized by syncytium and crush formation.Hemagglutination and blood adsorption tests were positive at 4℃and negative at the room temperature.Immunofluorescence staining exhibited specific apple green fluorescence. Conclusion The method for rapid culture and identification of human parainfluenza viruses in nasal swab specimens was successfully established, which can be used to obtain and identify parainfluenza viruses with virulence and biological activity in 2 days.

Objective To introduce a new spinal surgery navigation system based on structured light scanning(structured light navigation system,SLNS),and to compare accuracy of pedicle screw placement using SLNS,CT based navigation system and free hand technique.Methods Thirty-two calf vertebral pedicles,40 and 32 were placed with pedicle screws using SLNS,CT navigation system,and free hand technique,respectively.The pedicle breakage ratio,transverse section angle (TSA),sagittal section angle (SSA),screw offset deviation of each screw were detected according to CT images.Results The pedicle breakage ratio of pedicle screws in SLNS group,CT navigation group and free hand group were 6%(2./32),5%(2/40),25%(8/32),respectively.The difference between each of the two navigation groups and free hand group were statistically significant regarding frequency of screw misplacement.The difference between the two navigation systems was not obvious.The average SSA error and TSA error in SLNS group were 2.58°±2.74° and 4.26°±5.20°.For CT navigation group,they were 2.95°±2.61° and 3.13°±-2.75°.There was no statistical difference between the two navigation methods for the SSA or TSA error.There was no statistical difference in offset deviation among SLNS group,CT navigation group and free hand group.Conclusion The SLNS is a new and practical navigation system,which has similar accuracy with CT navigation system.

Objective The purpose of this study was to improve the success of organ donation and organ quality by analyzing the hemodynamic stability effect of 3-durgs therapy in brain death donor.Methods In this prospective observational study,we collected clinical data of brain death donors,who was admitted in the First Affiliated Hospital,Sun Yet-sen University from October 2015 to December 2016."3-durgs" emphasizes simultaneous use and includes vasopressin,thyroxine and corticosteroids.The assessment of hemodynamics is based on blood pressure,heart rate,blood oxygen,urine volume,and vasoactive drugs.According to the time of admission,included patients were divided into two groups:3-durgs therapy group and conventional therapy group therapy group;the clinical data were compared between two groups to analyze the effect of 3-durgs on hemodynamic stability.Furthermore,we used univariate and multivariable logistic regression analyses to assess associations between 3-durgs therapy and these variables.Results A total of 109 patients were included in the study;following the time sequence,54 cases enter into the conventional therapy group received conventional therapy,32 cases achieved hemodynamic stability;55 cases in 3-durgs group received 3-durgs and conventional therapy,45 cases achieved hemodynamic stability,3-durgs group is better than the conventional group.In the matter of high-does usage,single vasoactive agent can maintain hemodynamic stability rate and norepinephrine usage,3-durgs group is better than the conventional group.The univariate and multivariable analysis showed that the abnormal suprasellar cistern,midline shift,low free T3,axillary temperature more than 36.5 ℃ and central diabetes insipidus are associated with 3-durgs-hormone therapy.Conclusion 3-durgs therapy can contribute to maintain hemodynamic stability in brain death donors and reduce the usage of vasoactive agents,can improve the success rate of donations and improve the quality of occupied organ;meanwhile,the screened validities can predict the effectiveness of 3-durgs therapy.

Objective To investigate the distribution of high pathogenicity island(HPI)in multiple-drug-resistance gram-negative bacilli and analyze the protein sequence.Methods To amplify thefyuA-irp2 gene cluster of the 84 isolates by multiple polymerase chain reaction(PCR),the product was subsequently sequenced.Results The positive rate ofirpl,irp2,irp3,irp4 and fyuA was 40.48％,41,67％,5.95％,O％and 16.67％,respectively.Theamino sequence offyuA comefromEC06748,Kp7151 and PAE7 was usedto compare with AL590842,there are 100％identities.Amino sequence ofirp2 come from Kp49 and Kp51 have 99％identities with AAA27636.1,but amino sequence of irp2 come from EC04 and EC07 only have 90％identities with 1176840.The GenBank accession number is FJ211852 and FJ211851.Amino sequence ofirpl come fromKp 10,Kp49 and Kp51 have 99％identities with AL590842。and amino sequence ofirp3 come from EC03,Kp51,Kp10 and Kp49 have 97％identities with CAA73128.There are the same mutation among the same species,and different mutation among different species.Conclusion There was different extant mutant lost in thefy～t-i,v2 gene cluster in multiple-drug-resistanee gram-negative bacilli.

Objective By analyzing unusual movements of brain death organ donors before organ donation,to avoid misunderstanding and ensure the implementation of organ donation successfully.Methods Relevant clinical data of potential brain death organ donors admitted to the First Affiliated Hospital of Sun yat-sen University were prospectively collected between January 2016 and December 2017.The related parameters of neurological examination,neuroimaging examination and laboratory examination after brain death determination were dynamically recorded.The occurrence of limb,head and respiratory-like movement after brain death was defined as unusual movements,and the factors associated with unusual movements were screened by univariate and multivariate analysis.Results According to the inclusion criteria,164 patients were enrolled into this study.Twenty-two (13.4％) had unusual movements and duration was less than 72 h.Among them,21 (12.8％) had limbs unusual movements,6 (3.7％) had respiratory-like movement,5 (3％) owned both,and 4 (2.4％) had head rotation accompanied with limbs unusual movements.Univariate and multivariate analysis showed that axillary temperature ≤36 ℃,serum sodium ≤125 mmol/L,primary brain stem injury,spontaneous respiratory arrest time ≤72 h and age ≤ 18 years were associated with unusual movements.Conclusion During the clinical practice of brain death determination in China,the incidence of unusual movements is relatively low,and related to some factors,but it is extremely easy to cause misunderstanding.Correct cognition and interpretation are contributed to the successful implementation of organ donation.

Objective To identify the relative factors for "incongruent phenomenon" of brain electrical activity and cerebral blood flow during brain death determination for potential organ donors,and intensify the understanding and cognition of this phenomenon.Methods The clinical data of 127 potential donors accepted donation after brain death (DBD),admitted to our hospital from June 2018 to May 2019,were collected prospectively.All patients preferred brain electrical activity and cerebral blood flow assessments as the confirmatory tests of brain death determination.For patients with "incongruent phenomenon",further test of median nerve short latency evoked potential or brain electrical activity and cerebral blood flow assessments after waiting for 24 h were performed to confirm brain death determination again.Fifteen parameters,such as gender,age,time of spontaneous respiration arrest,blood pressure,operative types,neurological examination,neuroimaging index,and serum Na+ level,were selected;univariate and multivariate Logistic regression analyses were used to identify these risk factors related to "incongruent phenomenon".Results Among the 127 patients,22 patients (17.3％) appeared "incongruent phenomenon";17 (77.2％) had electrical silence earlier than cerebral blood flow arrest,and 5 (22.7％) had cerebral blood flow arrest earlier than electrical silence.Multivariate Logistic analysis showed that age ≤ 14 years (OR=6.250,95CI:1.201-32.220,P=0.028),systolic blood pressure ≥ 140 mmHg (OR=7.430,95CI:1.621-33.992,P=0.010),primary brain-stem injury (OR=15.890,95CI:3.042-82.930,P=0.006),spontaneous respiratory arrest time ≤72 h (OR=1 1.964,95CI:3.045-82.932,P=0.006),and unilateral/bilateral decompressive craniectomy (OR=16.281,95CI:1.590-89.785,P=0.001)were independent risk factors for "incongruent phenomenon".Conclusion "Incongruent phenomenon" is common in confirmatory test of brain death determination in China;patients with age≤14 years,systolic blood pressure ≥ 140 mmHg,primary brain-stem injury,spontaneous respiratory arrest time ≤ 72 h,and decompressive craniectomy (unilateral/bilateral) are more likely to have "incongruent phenomenon".

Objective: To establish a method for simultaneous and rapid detecting of the polymorphisms in Cytochrome P450 2C9 (CYP2C9), CYP2C19, CYP4F2, Vitamin K epoxide reductase (VKORC1) and ATP-binding cassette subfamily B member1 (ABCB1) gene, which were associated with warfarin and clopidogrel, based on liquid phase chip technology. Methods: Method establishment. The eight gene sequences near targeted sites related to warfarin and clopidogrel were found in Genbank, and the specific primers and probes were designed. Through multiple PCR amplification, followed by allele specific primer extension (ASPE), and MagPlex-Tag microspheres hybridization, the suspension array Luminex 200 system step-by-step, the genotypes were determined by fluorescence signal. The reaction system was optimized and its methodological evaluation was performed. 260 patients with antithrombotic therapy from Dongguan houjie hospital were recruited in this study form June 2017 to December 2018. The eight genotypes of the 260 patients were detected by the established method, and the results were compared with the sequencing results. Results: The results of 260 samples showed that allelic median fluorescence intensity (MFI) ratios of homozygotes (mutant/wild-type) were all greater than 0.9 or less than 0.1, and all the allelic MFI ratios of heterozygotes were between 0.3 and 0.6. The within run and between run coefficients of variance for allelic MFI ratios were lower than 6.4% and 10.9%, respectively. The minimum DNA template requirements was 0.75ng. The genotypes of 260 patients determined by the established method were completely concordant with the sequencing results. Conclusion A method was established successfully for rapid detecting the genotypes which associated with warfarin and clopidogrel based on liquid phase chip technology.